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The reaction sequence can be understood by analyzing each step separately.
In the first step, 2-methylbutanal reacts with hydrogen cyanide ($HCN$) to form a cyanohydrin.
The reaction proceeds through nucleophilic addition, where the cyanide ion ($CN^-$) attacks the electrophilic carbonyl carbon.
Pure $$HCN$$ is a weak acid and ionizes only slightly, so it does not provide a sufficient concentration of $$CN^-$$ ions. Therefore, a base catalyst is required to generate the active nucleophile.
Hence, reagent $$X$$ must be $$NaOH$$, which converts $$HCN$$ into $$CN^-$$. Using an acid such as $$HNO_3$$ would suppress the ionization of $$HCN$$ and inhibit the reaction.
The cyanohydrin formed in the first step contains both a hydroxyl group ($-OH$) and a nitrile group ($-C \equiv N$).
In the second step, treatment with $$LiAlH_4$$ reduces the nitrile group to a primary amine.
The reduction follows the transformation
$$-C \equiv N \longrightarrow -CH_2NH_2.$$
The hydroxyl group remains unchanged during this process.
Therefore, the carbon atom of the nitrile group is retained in the final product, and the product must contain a $$-CH_2NH_2$$ substituent attached to the carbon bearing the hydroxyl group.
Any structure showing the amino group attached directly as $$-NH_2$$ to that carbon is incorrect because it omits the carbon originally present in the cyanide group.
Hence,
Therefore, the correct answer is the first option.
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